Lubricating oil additive composition and method of making the same

ABSTRACT

An oil-soluble lubricating oil additive composition prepared by the process which comprises reacting a copolymer, with at least one ether compound and with at least one aromatic amine.

FIELD OF THE INVENTION

The present invention is directed to an improved dispersant additivecomposition that is used in engine oils; and it is also directed to theprocess of making the same.

BACKGROUND OF THE INVENTION

It is known to employ nitrogen containing dispersants and/or detergentsin the formulation of lubricating oil compositions. Many of the knowndispersant/detergent compounds are based on the reaction of analkenylsuccinic acid or anhydride with an amine or polyamine to producean alkenylsuccinimide or an alkenyl succinamic acid as determined byselected conditions of reaction. One problem facing the lubricantmanufacturer is dispersancy of particulate matter in internal combustionengines. Failure to have adequate particulate matter dispersancy mayresult in filter plugging, sludge accumulation, and oil thickening.

DESCRIPTION OF THE RELATED ART

Liu et al., U.S. Pat. No. 6,117,825, discloses a lubricating oilcomposition that comprises a major amount of an oil of lubricatingviscosity; and a minor amount of a synergistic combination of anantioxidant-dispersant additive and a dispersant additive, saidcombination comprising: (i) a polyisobutylene succinimide (PIBSAD) and(ii) an ethylene-propylene succinimide (LEPSAD).

Nalesnik, U.S. Pat. No. 5,138,688, discloses an additive compositioncomprising an oxidized ethylene copolymer or terpolymer of a C₃-C₁₀alpha-monoolefin and, optionally, a non-conjugated diene or triene whichhas been reacted with a formaldehyde compound and with an amino-aromaticpolyamine compound.

Günther et al., U.S. Pat. No. 6,512,055, discloses a copolymer obtainedby free radical copolymerization of at least one monoethylenicallyunsaturated C₄-C₆ dicarboxylic acid or anhydride thereof, an oligomer,and one monoethylenically unsaturated compound.

Günther et al., U.S. Pat. No. 6,284,716, discloses a lubricating oilcomposition comprising a lubricant oil and a copolymer obtained by freeradical copolymerization of at least one monoethylenically unsaturatedC₄-C₆ dicarboxylic acid or anhydride thereof, an oligomer, and onemonoethylenically unsaturated compound, wherein the copolymer is furtherreacted with an amine.

Harrison et al., U.S. Pat. No. 5,792,729, discloses a dispersantterpolymer and polysuccinimide compositions derived from theterpolymers. The terpolymer is obtained by free radical copolymerizationof an unsaturated acidic reagent, a 1-olefin, and a 1,1-disubstitutedolefin in the presence of a free radical initiator.

Barr et al., U.S. Pat. No. 5,670,462, discloses a lubricating oiladditive composition that is the reaction product of (i) a copolymerizedolefin and unsaturated carboxylic acylating agent monomer with a freeradical initiator and (ii) a succinimide prepared from an acyclichydrocarbyl substituted succinic acylating agent and a polyamine whereinthe hydrocarbyl substituted succinic acylating agent is prepared byreacting a polyolefin and an acylating agent under conditions such thatat least 75 mole % of the starting polyolefin is converted to thehydrocarbyl-substituted succinic acylating agent.

Harrison et al., U.S. Pat. No. 6,451,920, discloses copolymerizing apolyalkene and an unsaturated acidic reagent, followed by reacting anyunreacted polyalkene with the unsaturated acidic reagent at elevatedtemperatures in the presence of a strong acid.

Chung et al., U.S. Pat. Nos. 5,427,702 and 5,744,429, disclose a mixtureof derivatized ethylene-alpha olefin copolymers, wherein functionalgroups are grafted onto the copolymer. The functionalized copolymer ismixed with at least one of an amine, alcohol, including polyol, aminoalcohol etc. to form multi-functional viscosity index improver additivecomponents.

Harrison et al., U.S. Pat. No. 5,112,507, discloses novel copolymers ofunsaturated acidic reactants and high molecular weight olefins whereinat least 20% of the total high molecular weight olefin comprises thealkylvinylidene isomer which copolymers are useful as dispersants inlubricating oils and fuels and also may be used to preparepolysuccinimides and other post-treated additives useful in lubricatingoils and fuels.

SUMMARY OF THE INVENTION

In its broadest embodiment, the present invention is directed to anoil-soluble lubricating oil additive composition prepared by the processwhich comprises reacting

-   (A) at least one of the following copolymers:    -   (i) a copolymer obtained by free radical copolymerization of        components comprising:        -   (a) at least one monoethylenically unsaturated C₃-C₂₈            monocarboxylic acid or ester thereof, or C₄-C₂₈ dicarboxylic            acid, anhydride or ester thereof;        -   (b) at least one 1-olefin comprising about 2 to 40 carbon            atoms or at least one polyolefin comprising about 4 to 360            carbon atoms and having a terminal copolymerizable group in            the form of a vinyl, vinylidene or alkyl vinylidene group or            mixtures thereof; and        -   (c) at least one monoolefin compound which is            copolymerizable with the monomers of (a) and (b) and is            selected from the group consisting of:            -   (1) an alkyl vinyl ether and an allyl alkyl ether where                the alkyl group is hydroxyl, amino, dialkylamino or                alkoxy substituted or is unsubstituted, and containing 1                to 40 carbon atoms;            -   (2) an alkyl amine and an N-alkylamide of a                monoethylenically unsaturated mono- or dicarboxylic acid                of 3 to 10 carbon atoms where the alkyl substituent                contains 1 to 40 carbon atoms;            -   (3) an N-vinylcarboxamide of carboxylic acids of 1 to 8                carbon atoms;            -   (4) an N-vinyl substituted nitrogen-containing                heterocyclic compound; and            -   (5) at least one 1-olefin comprising about 2 to 40                carbon atoms or at least one polyolefin comprising about                4 to about 360 carbon atoms and having a terminal                copolymerizable group in the form of a vinyl, vinylidene                or alkyl vinylidene group or mixtures thereof, provided                that the olefin employed is not the same as the olefin                employed in (i)(b);    -   (ii) a copolymer obtained by reacting compound (i)(a) and        compound (i)(b) in the presence of a free radical initiator;    -   (iii) a copolymer obtained by (a) reacting compound (i)(a) with        compound (i)(b) or (i)(c) in a non-free radical catalyzed        reaction in the presence of copolymer (i) or copolymer (ii) or        both; or by (b) contacting copolymer (i) or copolymer (ii) or        both with the non-free radical catalyzed reaction product of        compound (i)(a) and compound (i)(b) or (i)(c); with-   (B) at least one ether compound selected from the group consisting    of an ether polyamine, a polyether polyamine, a polyether amino    alcohol, a polyether amino thiol, and a polyether polyol; and-   (C) at least one aromatic amine.

The present invention is also directed to a lubricating oil compositioncomprising a major amount of an oil of lubricating viscosity and a minoramount of the lubricating oil additive composition prepared by theprocess which comprises reacting

-   (A) at least one of the following copolymers:    -   (i) a copolymer obtained by free radical copolymerization of        components comprising:        -   (a) at least one monoethylenically unsaturated C₃-C₂₈            monocarboxylic acid or ester thereof, or C₄-C₂₈ dicarboxylic            acid, anhydride or ester thereof;        -   (b) at least one 1-olefin comprising about 2 to 40 carbon            atoms or at least one polyolefin comprising about 4 to 360            carbon atoms and having a terminal copolymerizable group in            the form of a vinyl, vinylidene or alkyl vinylidene group or            mixtures thereof; and        -   (c) at least one monoolefin compound which is            copolymerizable with the monomers of (a) and (b) and is            selected from the group consisting of:            -   (1) an alkyl vinyl ether and an allyl alkyl ether where                the alkyl group is hydroxyl, amino, dialkylamino or                alkoxy substituted or is unsubstituted, and containing 1                to 40 carbon atoms;            -   (2) an alkyl amine and an N-alkylamide of a                monoethylenically unsaturated mono- or dicarboxylic acid                of 3 to 10 carbon atoms where the alkyl substituent                contains 1 to 40 carbon atoms;            -   (3) an N-vinylcarboxamide of carboxylic acids of 1 to 8                carbon atoms;            -   (4) an N-vinyl substituted nitrogen-containing                heterocyclic compound; and            -   (5) at least one 1-olefin comprising about 2 to 40                carbon atoms or at least one polyolefin comprising about                4 to about 360 carbon atoms and having a terminal                copolymerizable group in the form of a vinyl, vinylidene                or alkyl vinylidene group or mixtures thereof, provided                that the olefin employed is not the same as the olefin                employed in (i)(b);    -   (ii) a copolymer obtained by reacting compound (i)(a) and        compound (i)(b) in the presence of a free radical initiator;    -   (iii) a copolymer obtained by (a) reacting compound (i)(a) with        compound (i)(b) or (i)(c) in a non-free radical catalyzed        reaction in the presence of copolymer (i) or copolymer (ii) or        both; or by (b) contacting copolymer (i) or copolymer (ii) or        both with the non-free radical catalyzed reaction product of        compound (i)(a) and compound (i)(b) or (i)(c); with-   (B) at least one ether compound selected from the group consisting    of an ether polyamine, a polyether polyamine, a polyether amino    alcohol, a polyether amino thiol, and a polyether polyol; and-   (C) at least one aromatic amine.

The present invention is also directed to a method of making alubricating oil additive composition which comprises reacting

-   (A) at least one of the following copolymers:    -   (i) a copolymer obtained by free radical copolymerization of        components comprising:        -   (a) at least one monoethylenically unsaturated C₃-C₂₈            monocarboxylic acid or ester thereof, or C₄-C₂₈ dicarboxylic            acid, anhydride or ester thereof;        -   (b) at least one 1-olefin comprising about 2 to 40 carbon            atoms or at least one polyolefin comprising about 4 to 360            carbon atoms and having a terminal copolymerizable group in            the form of a vinyl, vinylidene or alkyl vinylidene group or            mixtures thereof; and        -   (c) at least one monoolefin compound which is            copolymerizable with the monomers of (a) and (b) and is            selected from the group consisting of:            -   (1) an alkyl vinyl ether and an allyl alkyl ether where                the alkyl group is hydroxyl, amino, dialkylamino or                alkoxy substituted or is unsubstituted, and containing 1                to 40 carbon atoms;            -   (2) an alkyl amine and an N-alkylamide of a                monoethylenically unsaturated mono- or dicarboxylic acid                of 3 to 10 carbon atoms where the alkyl substituent                contains 1 to 40 carbon atoms;            -   (3) an N-vinylcarboxamide of carboxylic acids of 1 to 8                carbon atoms;            -   (4) an N-vinyl substituted nitrogen-containing                heterocyclic compound; and            -   (5) at least one 1-olefin comprising about 2 to 40                carbon atoms or at least one polyolefin comprising about                4 to about 360 carbon atoms and having a terminal                copolymerizable group in the form of a vinyl, vinylidene                or alkyl vinylidene group or mixtures thereof, provided                that the olefin employed is not the same as the olefin                employed in (i)(b);    -   (ii) a copolymer obtained by reacting compound (i)(a) and        compound (i)(b) in the presence of a free radical initiator;    -   (iii) a copolymer obtained by (a) reacting compound (i)(a) with        compound (i)(b) or (i)(c) in a non-free radical catalyzed        reaction in the presence of copolymer (i) or copolymer (ii) or        both; or by (b) contacting copolymer (i) or copolymer (ii) or        both with the non-free radical catalyzed reaction product of        compound (i)(a) and compound (i)(b) or (i)(c); with-   (B) at least one ether compound selected from the group consisting    of an ether polyamine, a polyether polyamine, a polyether amino    alcohol, a polyether amino thiol, and a polyether polyol; and-   (C) at least one aromatic amine.

Accordingly, the present invention relates to multi-functionallubricating oil additives which are useful as dispersants in an internalcombustion engine.

DETAILED DESCRIPTION OF THE INVENTION

While the invention is susceptible to various modifications andalternative forms, specific embodiments thereof and are herein describedin detail. It should be understood, however, that the description hereinof specific embodiments is not intended to limit the invention to theparticular forms disclosed, but on the contrary, the intention is tocover all modifications, equivalents, and alternatives falling withinthe spirit and scope of the invention as defined by the appended claims.

DEFINITIONS

The following terms used with the description are defined as such:

The term “PIB” is an abbreviation for polyisobutene.

The term “PIBSA” is an abbreviation for polyisobutenyl succinicanhydride.

The term “polyPIBSA” refers to a class of copolymers employed within thescope of the present invention which are copolymers of polyisobutene anda monoethylenically unsaturated C₃-C₂₈ monocarboxylic acid or esterthereof, or a C₄-C₂₈ dicarboxylic acid, anhydride or ester thereof whichhave carboxyl groups, preferably succinic groups, and polyisobutylgroups. The preferred polyPIBSA is a copolymer of polyisobutene andmaleic anhydride having the general formula:

wherein n is one or greater; R₁, R₂, R₃ and R₄ are selected fromhydrogen, methyl and polyisobutyl having at least about 30 carbon atoms(preferably at least about 50 carbon atoms) wherein either R₁ and R₂ arehydrogen and one of R₃ and R₄ is methyl and the other is polyisobutyl,or R₃ and R₄ are hydrogen and one of R₁ and R₂ is methyl and the otheris polyisobutyl. The polyPIBSA copolymer may be alternating, block, orrandom.

The term “succinic group” refers to a group having the formula:

wherein W and Z are independently selected from the group consisting of—OH, —Cl, —O— lower alkyl or taken together are —O— to form a succinicanhydride group. The term “—O— lower alkyl” is meant to include alkoxyof 1 to 6 carbon atoms.

The term “degree of polymerization” refers to the average number ofrepeating structural units in the polymer chain.

The term “terpolymer” refers to a polymer derived from the free radicalcopolymerization of at least 3 monomers.

The term “1-olefin” refers to a monounsaturated olefin that has thedouble bond in the 1-position. They can also be called alpha-olefins,and have the following structure:CH₂═CHRwhere R is the rest of the olefin molecule.

The term “1,1-disubstituted olefin” refers to a disubstituted olefin,also called a vinylidene olefin, that has the following structure:CH₂═CR¹R²where R¹ and R² are the same or different, and constitute the rest ofthe olefin molecule. Preferably, either R¹ or R² is a methyl group, andthe other is not.

The term “succinimide” is understood in the art to include many of theamide, imide, etc. species which are also formed by the reaction of asuccinic anhydride with an amine. The predominant product, however, issuccinimide and this term has been generally accepted as meaning theproduct of a reaction of an alkenyl- or alkyl-substituted succinic acidor anhydride with an amine. Alkenyl or alkyl succinimides are disclosedin numerous references and are well known in the art. Certainfundamental types of succinimides and related materials encompassed bythe term of art “succinimide” are taught in U.S. Pat. Nos. 2,992,708;3,018,291; 3,024,237; 3,100,673; 3,219,666; 3,172,892; and 3,272,746,the disclosures of which are hereby incorporated by reference.

The term “polysuccinimide” refers to the reaction product of a succinicgroup-containing copolymer with an amine.

The term “alkenyl or alkylsuccinic acid derivative” refers to astructure having the formula:

wherein L and M are independently selected from the group consisting of—OH, —Cl, —O—, lower alkyl or taken together are —O— to form an alkenylor alkylsuccinic anhydride group.

The term “alkylvinylidene” or “alkylvinylidene isomer” refers to highmolecular weight olefins and polyalkylene components having thefollowing vinylindene structure:

wherein R is alkyl or substituted alkyl of sufficient chain length togive the resulting molecule solubility in lubricating oils and fuels,thus R generally has at least about 30 carbon atoms, preferably at leastabout 50 carbon atoms and R_(v) is lower alkyl of about 1 to about 6carbon atoms.

The term “soluble in lubricating oil” refers to the ability of amaterial to dissolve in aliphatic and aromatic hydrocarbons such aslubricating oils or fuels in essentially all proportions.

The term “high molecular weight olefins” refers to olefins (includingpolymerized olefins having a residual unsaturation) of sufficientmolecular weight and chain length to lend solubility in lubricating oilto their reaction products. Typically olefins having about 30 carbons ormore suffice.

The term “high molecular weight polyalkyl” refers to polyalkyl groups ofsufficient molecular weight such that the products prepared having suchsufficient molecular weight are soluble in lubricating oil. Typicallythese high molecular weight polyalkyl groups have at least about 30carbon atoms, preferably at least about 50 carbon atoms. These highmolecular weight polyalkyl groups may be derived from high molecularweight polyolefins.

The term “amino” refers to —NR₁R₂ wherein R₁ and R₂ are independentlyhydrogen or a hydrocarbyl group.

The term “alkyl” refers to both straight- and branched-chain alkylgroups.

The term “lower alkyl” refers to alkyl groups having 1 to about 6 carbonatoms and includes primary, secondary and tertiary alkyl groups. Typicallower alkyl groups include, for example, methyl, ethyl, n-propyl,isopropyl, n-butyl, sec-butyl, t-butyl, n-pentyl, n-hexyl and the like.

The term “polyalkyl” refers to an alkyl group that is generally derivedfrom polyolefins which are polymers or copolymers of mono-olefins,particularly 1-mono-olefins, such as ethylene, propylene, butylene, andthe like. Preferably, the mono-olefin employed will have 2 to about 24carbon atoms, and more preferably, about 3 to 12 carbon atoms. Morepreferred mono-olefins include propylene, butylene, particularlyisobutylene, 1-octene and 1-decene. Preferred, polyolefins prepared fromsuch mono-olefins include polypropylene, polybutene, especiallypolyisobutene.

The Lubricating Oil Additive Composition

One embodiment of the present invention is an oil-soluble lubricatingoil additive composition prepared by the process which comprisesreacting

-   (A) at least one of the following copolymers:    -   (i) a copolymer obtained by free radical copolymerization of        components comprising:        -   (a) at least one monoethylenically unsaturated C₃-C₂₈            monocarboxylic acid or ester thereof, or C₄-C₂₈ dicarboxylic            acid, anhydride or ester thereof;        -   (b) at least one 1-olefin comprising about 2 to 40 carbon            atoms or at least one polyolefin comprising about 4 to 360            carbon atoms and having a terminal copolymerizable group in            the form of a vinyl, vinylidene or alkyl vinylidene group or            mixtures thereof; and        -   (c) at least one monoolefin compound which is            copolymerizable with the monomers of (a) and (b) and is            selected from the group consisting of:            -   (1) an alkyl vinyl ether and an allyl alkyl ether where                the alkyl group is hydroxyl, amino, dialkylamino or                alkoxy substituted or is unsubstituted, and containing 1                to 40 carbon atoms;            -   (2) an alkyl amine and an N-alkylamide of a                monoethylenically unsaturated mono- or dicarboxylic acid                of 3 to 10 carbon atoms where the alkyl substituent                contains 1 to 40 carbon atoms;            -   (3) an N-vinylcarboxamide of carboxylic acids of 1 to 8                carbon atoms;            -   (4) an N-vinyl substituted nitrogen-containing                heterocyclic compound; and            -   (5) at least one 1-olefin comprising about 2 to 40                carbon atoms or at least one polyolefin comprising about                4 to about 360 carbon atoms and having a terminal                copolymerizable group in the form of a vinyl, vinylidene                or alkyl vinylidene group or mixtures thereof, provided                that the olefin employed is not the same as the olefin                employed in (i)(b);    -   (ii) a copolymer obtained by reacting compound (i)(a) and        compound (i)(b) in the presence of a free radical initiator;    -   (iii) a copolymer obtained by (a) reacting compound (i)(a) with        compound (i)(b) or (i)(c) in a non-free radical catalyzed        reaction in the presence of copolymer (i) or copolymer (ii) or        both; or by (b) contacting copolymer (i) or copolymer (ii) or        both with the non-free radical catalyzed reaction product of        compound (i)(a) and compound (i)(b) or (i)(c); with-   (B) at least one ether compound selected from the group consisting    of an ether polyamine, a polyether polyamine, a polyether amino    alcohol, a polyether amino thiol, and a polyether polyol; and-   (C) at least one aromatic amine.    Copolymer (i)    (a) The Monoethylenically Unsaturated Monocarboxylic Acid or Ester    Thereof or Dicarboxylic Acid, Anhydride or Ester Thereof

In the present invention, at least one monoethylenically unsaturatedC₃-C₂₈ monocarboxylic acid or ester thereof, or C₄-C₂₈ dicarboxylicacid, anhydride or ester thereof is used to prepare the copolymers ofcopolymer (i). Preferably the at least one monoethylenically unsaturatedC₃-C₂₈ monocarboxylic acid or ester thereof, or C₄-C₂₈ dicarboxylicacid, anhydride or ester thereof is a dicarboxylic acid, anhydride orester thereof.

The general formula of the preferred dicarboxylic acid, anhydride orester thereof is as follows:

wherein X and X′ are the same or different, provided that at least oneof X and X′ is a group that is capable of reacting to esterify alcohols,form amides or amine salts with ammonia or amines, form metal salts withreactive metals or basically reacting metal compounds and otherwisefunction as acylating agents. Typically, X and/or X′ is —OH,—O-hydrocarbyl, OM+ where M+ represents one equivalent of a metal,ammonium or amine cation, —NH2, —Cl, —Br, and taken together X and X′can be —O— so as to form an anhydride. Preferably X and X′ are such thatboth carboxylic functions can enter into acylation reactions. Maleicanhydride is a preferred reactant. Other suitable reactants includeelectron-deficient olefins such as monophenyl maleic anhydride;monomethyl, dimethyl, monochloro, monobromo, monofluoro, dichloro anddifluoro maleic anhydride: N-phenylmaleimide and other substitutedmaleimides, isomaleimides; fumaric acid, maleic acid, alkyl hydrogenmaleates and fumarates, dialkyl fumarates and maleates, fumaronilicacids and maleanic acids; and maleonitrile and fumaronitrile.

Suitable monomers for (a) are monoethylenically unsaturated dicarboxylicacids or anhydrides of 4 to 28 carbon atoms selected from the groupcomprising maleic acid, fumaric acid, itaconic acid, mesaconic acid,methylenemalonic acid, citraconic acid, maleic anhydride, itaconicanhydride, citraconic anhydride and methylenemalonic anhydride andmixtures of these with one another, among which maleic anhydride ispreferred.

Other suitable monomers are monoethylenically unsaturatedC₃-C₂₈-monocarboxylic acids selected from the group comprising acrylicacid, methacrylic acid, dimethacrylic acid, ethylacrylic acid, crotonicacid, allylacetic acid and vinylacetic acid, among which acrylic andmethacrylic acid are preferred. Another group of suitable monomers isC₁-C₄₀ alkyl esters of monoethylenecially unsaturated C₃-C₁₀ mono- ordicarboxylic acids such as ethyl acrylate, butyl acrylate, 2-ethylacrylate, decyl acrylate, docedyl acrylate, loctadecyl acrylate and theesters of industrial alcohol mixtures of 14 to 28 carbon atoms, ethylmethacrylate, 2-ethylhexyl methacrylate, decyl methacrylate, octadecylmethacrylate, monobutyl maleate, dibutyl maleate, monodecyl maleate,didodecyl maleate, monooctadecyl maleate, and dioctadecyl maleate.

(b) The 1-Olefin or Polyolefin

In the present invention at least one 1-olefin comprising about 2 to 40carbon atoms or at least one polyolefin comprising about 4 to 360 carbonatoms and having a terminal copolymerizable group in the form of vinyl,vinylidene or alkyl vinylidene group is employed.

Suitable 1-olefins for preparing copolymer (i) comprise about 2 to 40carbon atoms, preferably 6 to 30 carbon atoms, such as decene, dodecene,octadecene and mixtures of C₂₀-C₂₄-1-olefins and C₂₄-C₂₈-1-olefins, morepreferably 10 to 20 carbon atoms. Preferably 1-olefins, which are alsoknown as alpha olefins, with molecular weights in the range 100-4,500 ormore are preferred, with molecular weights in the range of 200-2,000being more preferred. For example, alpha olefins obtained from thethermal cracking of paraffin wax. Generally, these olefins range from 5to 20 carbon atoms in length. Another source of alpha olefins is theethylene growth process which gives even number carbon olefins. Anothersource of olefins is by the dimerization of alpha olefins over anappropriate catalyst such as the well known Ziegler catalyst. Internalolefins are easily obtained by the isomerization of alpha olefins over asuitable catalyst such as silica.

Preferably, 1-olefins from C₆-C₃₀ are used because these materials arecommercially readily available, and because they offer a desirablebalance of the length of the molecular tail, and the solubility of theterpolymer in nonpolar solvents. Mixtures of olefins may also beemployed.

Suitable polyolefins for preparing copolymer (i) are polyolefinscomprising about 4 to about 360 carbon atoms. These polymers have anaverage molecular weight (M_(n)) of from about 56 to about 5000 g/mol.Examples of these are oligomers of ethylene, of butene, includingisobutene, and of branched isomers of pentene, hexene, octene and ofdecene, the copolymerizable terminal group of the oligomer being presentin the form of a vinyl, vinylidene or alkylvinylidene group,oligopropenes and oligopropene mixtures of 9 to 200 carbon atoms and inparticular oligoisobutenes, as obtainable, for example, according toDE-A 27 02 604, corresponding U.S. Pat. No. 4,152,499, are preferred.Mixtures of the stated oligomers are also suitable, for example,mixtures of ethylene and other alpha olefins. Other suitable polyolefinsare described in U.S. Pat. No. 6,030,930 which is herein incorporated byreference. The molecular weights of the oligomers may be determined in aconventional manner by gel permeation chromatography.

The copolymerizable polyolefin that is reacted with the unsaturatedmono- or di-carboxylic reactant are polymers comprising a major amountof C₂-C₈ mono-olefin, e.g., ethylene, propylene, butylene, isobutyleneand pentene. These polymers can be homopolymers such as polyisobutyleneas well as copolymers of 2 or more such olefins such as copolymers of:ethylene and propylene, butylene, and isobutylene, etc. Other copolymersinclude those in which a minor amount of the copolymer monomers, e.g., 1to 20 mole % is a C₄-C₈ nonconjugated diolefin, e.g., a copolymer ofisobutylene and butadiene or a copolymer of ethylene, propylene and1,4-hexadiene, etc.

The polyolefin polymer usually contains from about 4 to 360 carbonatoms, although preferably 8 to 200 carbon atoms; and more preferably 12to 175 carbon atoms.

Since the high molecular weight olefins used to prepare the copolymersof the present invention are generally mixtures of individual moleculesof different molecular weights, individual copolymer molecules resultingwill generally contain a mixture of high molecular weight polyalkylgroups of varying molecular weight. Also, mixtures of copolymermolecules having different degrees of polymerization will be produced.

The copolymers of the present invention have an average degree ofpolymerization of 1 or greater, preferably from about 1.1 to about 20,and more preferably from about 1.5 to about 10.

(c) The Mono-Olefin Compound

The present invention employs at least one monoolefin compound which iscopolymerizable with the monomers of (a) and (b) and is selected fromthe group consisting of:

-   (1) an alkyl vinyl ether and an allyl alkyl ether where the alkyl    group is hydroxyl, amino, dialkylamino or alkoxy substituted or is    unsubstituted, and containing 1 to 40 carbon atoms;-   (2) an alkyl amine and an N-alkylamide of a monoethylenically    unsaturated mono- or dicarboxylic acid of 3 to 10 carbon atoms where    the alkyl substituent contains 1 to 40 carbon atoms;-   (3) an N-vinylcarboxamide of carboxylic acids of 1 to 8 carbon    atoms;-   (4) an N-vinyl substituted nitrogen-containing heterocyclic    compound; and-   (5) at least one 1-olefin comprising about 2 to 40 carbon atoms or    at least one polyolefin comprising about 4 to about 360 carbon atoms    and having a terminal copolymerizable group in the form of a vinyl,    vinylidene or alkyl vinylidene group or mixtures thereof, provided    that the olefin employed is not the same as the olefin employed in    (i)(b);    (1)    -   Suitable monomers include the following: vinyl and allyl alkyl        ethers where the alkyl radical is of 1 to 40 carbon atoms are        also suitable, and the alkyl radical may carry further        substituents, such as hydroxyl, amino, dialkyamino or alkoxy.        Examples are methyl vinyl ether, ethyl vinyl ether, propyl vinyl        ether, isobutyl vinyl ether, 2-ethylhexyl vinyl ether,        decylvinyl ether, dodecyl vinyl ether, octadecyl vinyl ether,        2-(diethylyamino)ethyl vinyl ether, 2-(di-n-butylamino)ethyl        vinyl ether, and the corresponding allyl ethers.        (2)        Another group of monomers comprises C₁-C₄₀ alkyl amines and        C₁-C₄₀-N-alkylamides of monoethylenically unsaturated        C₃-C₁₀-mono- or dicarboxylic acids, such as dimethylaminoethyl        acrylate, diethylaminoethyl acrylate, dibutylaminoethyl        methacrylate, acrylamide, methacrylamide,        N-tert-butylacrylamide, N-octylacrylamide,        N,N′-dibutylacrylamide, N-dodecylmethacrylamide and        N-octadecylmethacrylamide.        (3)        Another group of monomers includes the following:        N-vinylcarboxamides of carboxylic acids of 1 to 8 carbon atoms,        such as N-vinylformamide, N-vinyl-N-methylformamide,        N-vinylacetamide, N-vinyl-N-methylacetramide,        N-vinyl-N-ethylacetamide, N-vinyl-N-methylpropionamide and        N-vinylpropionamide.        (4)        Another group of monomers includes the following: N-vinyl        compounds of nitrogen-containing heterocyles, such as        N-vinylimidazole, N-vinylmethylimidazole, N-vinylpyrrolidone and        N-vinylcaprolactam.        (5)        Suitable 1-olefins comprise about 2 to 40 carbon atoms,        preferably 8 to 30 carbon atoms, such as decene, dodecene,        octadecene and mixtures of C₂₀-C₂₄-1-olefins and        C₂₄-C₂₈-1-olefins. Preferably 1-olefins, which are also known as        alpha olefins, with molecular weights in the range of 28-560 are        preferred, with molecular weights in the range of 112-420 being        more preferred. For example, alpha olefins obtained from the        thermal cracking of paraffin wax may be employed. Generally,        these olefins range from 5 to 20 carbon atoms in length. Another        source of alpha olefins is the ethylene growth process which        gives even number carbon olefins. Another source of olefins is        by the dimerization of alpha olefins over an appropriate        catalyst such as the well known Ziegler catalyst. Internal        olefins are easily obtained by the isomerization of alpha        olefins over a suitable catalyst such as silica. Preferably,        1-olefins from C₁₀-C₃₀ are used because these materials are        commercially readily available, and because they offer a        desirable balance of the length of the molecular tail, and the        solubility of the terpolymer in nonpolar solvents. Mixtures of        olefins are also suitable.        Preparation of Copolymer (i)

Copolymer reactant (i) may be prepared from well known methods which aredescribed in the art including, but not limited to, those methods whichare disclosed in the following patents, which are herein incorporated byreference: Harrison et al., U.S. Pat. No. 5,792,729; Günther et al.,U.S. Pat. No. 6,284,716; and Günther et al., U.S. Pat. No. 6,512,055.

In one embodiment of the present invention the copolymer reactant is apolyalkenyl succinic anhydride terpolymer. These terpolymers arecomposed of at least one of monomers (a) to (c) as described herein.

Typically, the terpolymers of this invention contain at least one ofmonomers (a) to (c) three components comprising of a monocarboxylic acidor ester thereof, or a dicarboxlylic acid or anhydride or ester thereof;a branched olefin; and a monoolefin. In general, these components reactto form terpolymers which can be random terpolymers or alternatingterpolymers or block terpolymers and can be prepared by known proceduresfor making copolymers. The monocarboyxlic acid or ester thereof ordicarboxylic acid or anhydride or ester thereof is selected from thosewhich were previously disclosed, preferably maleic anhydride.

The degree of polymerization of the terpolymers can vary over a widerange. In general, terpolymers of high molecular weight can be producedat low temperatures, and terpolymers of low molecular weight can beproduced at high temperatures.

The terpolymerization is conducted in the presence of a suitable freeradical initiator. Examples of suitable polymerization initiators areperoxide compounds, such as terybutyl perpivalate, terybutylperneocecanoate, tery-butylperethylhexanoate, tertbutylperisobutyrate,di-tert-butyl peroxide, di-tert-amyl peroxide, diacetyl peroxydicaronateand dicyclohexyldicaronate, or azo compounds, such as2,2′-azobisisobutyrontrile. The intiators may be used alone or as amixture with one another. Redox co-initiators may also be present.Preferably, the initiator is a peroxide type initiator, e.g.,di(t-butyl) peroxide, dicumyl peroxide or azo type initiator, e.g.,isobutylnitrile type initiators. Procedures for preparing poly 1-olefincopolymers are, for example, described in U.S. Pat. Nos. 3,560,455 and4,240,916, hereby incorporated by reference in their entirety. Thoseprocedures could be used to prepare terpolymers. Both patents alsodescribe a variety of initiators.

Copolymer (i), wherein a second olefin is employed in the reaction, canbe prepared in the same manner as copolymer (ii) which is describedbelow.

Copolymer (ii)

In another embodiment of the present invention, the copolymer reactantis a copolymer obtained by reacting (a) at least one monoethylenicallyunsaturated C₃-C₂₈ monocarboxylic acid or ester thereof, or a C₄-C₂₈dicarboxylic acid, anhydride or ester thereof and (b) at least onecopolymerizable polymer composed of at least 3 olefin molecules ofpropene or of a branched 1-olefin of 4 to 10 carbon atoms, having anumber average molecular weight M_(n) of from about 112 to about 5000,and having a terminal copolymerizable group in the form of a vinyl,vinylidene or alkyl vinylidene group in the presence of a free radicalinitiator.

Thus, preferred copolymers of the present invention are prepared byreacting a “reactive” high molecular weight olefin in which a highproportion of unsaturation, at least about 20% is in the alkylvinylideneconfiguration, e.g.,

wherein R and R_(v) is an alkyl or substituted alkyl of sufficient chainlength to give the resulting molecule stability in lubricating oils andfuels, thus R generally has at least about 30 carbon atoms, preferablyat least about 50 carbon atoms and R_(v) is a lower alkyl of about 1 toabout 6 carbon atoms, with an unsaturated acidic reactant in thepresence of a free radical initiator. The product copolymer hasalternating polyalkylene and succinic groups and has an average degreeof polymerization of 1 or greater.

The preferred copolymers (ii) of the present invention have the generalformula:

wherein W′ and Z′ are independently selected from the group consistingof —OH, —O— lower alkyl or taken together are —O— to form a succinicanhydride group, n is one or greater; and R₁, R₂, R₃ and R₄ are selectedfrom hydrogen, lower alkyl of 1 to 6 carbon atoms, and high molecularweight polyalkyl wherein either R₁ and R₂ are hydrogen and one of R₃ andR₄ is lower alkyl and the other is high molecular weight polyalkyl, orR₃ and R₄ are hydrogen and one of R₁ and R₂ is lower alkyl and the otheris high molecular weight polyalkyl.

Copolymer (ii) may be alternating, block, or random.

In a preferred embodiment, when maleic anhydride is used as thereactant, the reaction produces copolymers predominately of thefollowing formula:

wherein n is about 1 to about 100, preferably about 2 to about 20, morepreferably 2 to 10, and R₁, R₂, R₃ and R₄ are selected from hydrogen,lower alkyl of about 1 to 6 carbon atoms and higher molecular weightpolyalkyl, wherein either R₁ and R₂ are hydrogen and one of R₃ and R₄ islower alkyl and the other is high molecular weight polyalkyl or R₃ andR₄ are hydrogen and one of R₁ and R₂ is lower alkyl and the other ishigh molecular weight polyalkyl.

Preferably, the high molecular weight polyalkyl group has at least about30 carbon atoms (preferably at least about 50 carbon atoms). Preferredhigh molecular weight polyalkyl groups include polyisobutyl groups.Preferred polyisobutyl groups include those having average molecularweights of about 500 to about 5000, more preferably from about 900 toabout 2500. Preferred lower alkyl groups include methyl and ethyl;especially preferred lower alkyl groups include methyl.

A particularly preferred class of olefin polymers comprises thepolybutenes, which are prepared by polymerization of isobutene. Thesepolybutenes are readily available commercial materials well known tothose skilled in the art. Disclosures thereof will be found, forexample, in U.S. Pat. Nos. 4,152,499 and 4,605,808, which are hereinincorporated by reference for their disclosures of suitable polybutenes.

Preferably, 1,1-disubstituted olefins are used to provide a highmolecular weight, oil soluble tail in the terpolymer. Preferably the1,1-disubstituted olefin has an average M_(n) of from 500 to 5000. Oneparticularly useful 1,1-disubstituted olefin is a 1,1-disubstitutedpolyisobutylene, such as methylvinylidene polyisobutylene.

Preferably the copolymerizable polymer comprises a high molecular weightpolyalkyl group which is derived from a high molecular weight olefin.The high molecular weight olefins used in the preparation of thecopolymers of the present invention are of sufficiently long chainlength so that the resulting composition is soluble in and compatiblewith mineral oils, fuels and the like; and the alkylvinylidene isomer ofthe high molecular weight olefin comprises at least about 20% of thetotal olefin composition.

Such high molecular weight olefins are generally mixtures of moleculeshaving different molecular weights and can have at least one branch per6 carbon atoms along the chain, preferably at least one branch per 4carbon atoms along the chain, and particularly preferred that there beabout one branch per 2 carbon atoms along the chain. These branchedchain olefins may conveniently comprise polyalkenes prepared by thepolymerization of olefins of from 3 to 6 carbon atoms, and preferablyfrom olefins of from 3 to 4 carbon atoms, and more preferably frompropylene or isobutylene. The addition-polymerizable olefins employedare normally 1-olefins. The branch may be of from 1 to 4 carbon atoms,more usually of from 1 to 2 carbon atoms and preferably methyl.

The preferred alkylvinylidene isomer comprises a methyl- orethylvinylidene isomer, more preferably the methylvinylidene isomer.

The especially preferred high molecular weight olefins used to preparethe copolymers of the present invention are polyisobutenes whichcomprise at least about 20% of the more reactive methylvinylideneisomer, preferably at least 50% and more preferably at least 70%.Suitable polyisobutenes include those prepared using BF₃ catalysis. Thepreparation of such polyisobutenes in which the methylvinylidene isomercomprises a high percentage of the total composition is described inU.S. Pat. Nos. 4,152,499 and 4,605,808.

Preparation of Copolymer (ii)

As noted above, copolymer (ii) of the present invention is prepared byreacting an olefin and an unsaturated acidic reactant in the presence ofa free radical initiator. The process of the preparation of copolymer(ii) is described in Harrison, U.S. Pat. No. 5,112,507, which is hereinincorporated by reference in its entirety.

The reaction may be conducted at a temperature of about −30° C. to about210° C., preferably from about 40° C. to about 160° C. The degree ofpolymerization is inversely proportional to temperature. Accordingly,for the preferred high molecular weight copolymers, it is advantageousto employ lower reaction temperatures. For example, if the reaction isconducted at about 138° C., an average degree of polymerization of about1.3 was obtained. However, if the reaction was conducted at atemperature of about 40° C., an average degree of polymerization ofabout 10.5 was obtained.

The reaction may be conducted neat, that is, both the high molecularweight olefin, acidic reactant and the free radical initiator arecombined in the proper ratio, and then stirred at the reactiontemperature.

Alternatively, the reaction may be conducted in a diluent. For example,the reactants may be combined in a solvent. Suitable solvents includethose in which the reactants and free radical initiator are soluble andinclude acetone, tetrahydrofuran, chloroform, methylene chloride,dichloroethane, toluene, dioxane, chlorobenzene, xylenes, or the like.After the reaction is complete, volatile components may be stripped off.When a diluent is employed, it is preferably inert to the reactants andproducts formed and is generally used in an amount sufficient to ensureefficient mixing.

In the preparation of polyPIBSA, improved results are obtained by usingPIBSA or polyPIBSA as a solvent for the reaction.

In general, the copolymerization can be initiated by any free radicalinitiator. Such initiators are well known in the art. However, thechoice of free radical initiator may be influenced by the reactiontemperature employed.

The preferred free-radical initiators are the peroxide-typepolymerization initiators and the azo-type polymerization initiators.Radiation can also be used to initiate the reaction, if desired.

The peroxide-type free-radical initiator can be organic or inorganic,the organic having the general formula: R₃OOR′₃ where R₃ is any organicradical and R′₃ is selected from the group consisting of hydrogen andany organic radical. Both R₃ and R′₃ can be organic radicals, preferablyhydrocarbon, aroyl, and acyl radicals, carrying, if desired,substituents such as halogens, etc. Preferred peroxides includedi-tert-butyl peroxide, dicumyl peroxide, and di-tert-amyl peroxide.

Examples of other suitable peroxides, which in no way are limiting,include benzoyl peroxide; lauroyl peroxide; other tertiary butylperoxides; 2,4-dichlorobenzoyl peroxide; tertiary butyl hydroperoxide;cumene hydroperoxide; diacetyl peroxide; acetyl hydroperoxide;diethylperoxycarbonate; tertiary butyl perbenzoate; and the like.

The azo-type compounds, typified by alpha,alpha′-azobisisobutyronitrile,are also well-known free-radical promoting materials. These azocompounds can be defined as those having present in the molecule group—N═N wherein the balances are satisfied by organic radicals, at leastone of which is preferably attached to a tertiary carbon. Other suitableazo compounds include, but are not limited to, p-bromobenzenediazoniumfluoroborate; p-tolyldiazoaminobenzene; p-bromobenzenediazoniumhydroxide; azomethane and phenyldiazonium halides. A suitable list ofazo-type compounds can be found in U.S. Pat. No. 2,551,813, issued May8, 1951 to Paul Pinkney.

The amount of initiator to employ, exclusive of radiation, of course,depends to a large extent on the particular initiator chosen, the highmolecular olefin used and the reaction conditions. The initiator must,of course, be soluble in the reaction medium. The usual concentrationsof initiator are between 0.001:1 and 0.2:1 moles of initiator per moleof acidic reactant, with preferred amounts between 0.005:1 and 0.10:1.

The polymerization temperature must be sufficiently high to break downthe initiator to produce the desired free-radicals. For example, usingbenzoyl peroxide as the initiator, the reaction temperature can bebetween about 75° C. and about 90° C., preferably between about 80° C.and about 85° C. higher and lower temperatures can be employed, asuitable broad range of temperatures being between about 20° C. andabout 200° C., with preferred temperatures between about 50° C. andabout 150° C.

The reaction pressure should be sufficient to maintain the solvent inthe liquid phase. Pressures can therefore vary between about atmosphericand 100 psig or higher, but the preferred pressure is atmospheric.

The reaction time is usually sufficient to result in the substantiallycomplete conversion of the acidic reactant and high molecular weightolefin to copolymer. The reaction time is suitable between one and 24hours, with preferred reaction times between 2 and 10 hours.

As noted above, the subject reaction is a solution-type polymerizationreaction. The high molecular weight olefin, acidic reactant, solvent andinitiator can be brought together in any suitable manner. The importantfactors are intimate contact of the high molecular weight olefin andacidic reactant in the presence of a free-radical producing material.The reaction, for example, can be conducted in a batch system where thehigh molecular weight olefin is added all initially to a mixture ofacidic reactant, initiator and solvent or the high molecular weightolefin can be added intermittently or continuously to the reactor.Alternatively, the reactants may be combined in other orders; forexample, acidic reactant and initiator may be added to high molecularweight olefin in the reactor. In another manner, the components in thereaction mixture can be added continuously to a stirred reactor withcontinuous removal of a portion of the product to a recovery train or toother reactors in series. In yet another manner, the reaction may becarried out in a batch process, wherein the high molecular weight olefinis added initially to the reactor, and then the acidic reactant and theinitiator are added gradually over time. The reaction can also suitablytake place in a coil-type reactor where the components are added at oneor more points along the coil.

Copolymer (iii)

In one embodiment, copolymer reactant (iii) is obtained by a copolymerobtained by (a) reacting compound (i)(a) with compound (i)(b) or (i)(c)in a non-free radical catalyzed reaction in the presence of copolymer(i) or copolymer (ii) or both; or by (b) contacting copolymer (i) orcopolymer (ii) or both with the non-free radical catalyzed reactionproduct of compound (i)(a) and compound (i)(b) or (i)(c).

Preparation of Copolymer (iii)

A process for the preparation of copolymer (iii) is described, forexample, in Harrison, et al., U.S. Pat. No. 6,451,920, which is hereinincorporated by reference in its entirety.

In process step (a) above, any unreacted olefin, generally the morehindered olefins, i.e., the beta-vinylidene, that do not react readilywith the monoethylenically unsaturated C₃-C₂₈ monocarboxylic acid orester thereof, or C₄-C₂₈ dicarboxylic acid or an anhydride or esterthereof, under free radical conditions, are reacted withmonoethylenically unsaturated C₃-C₂₈ monocarboxylic acid or esterthereof, or C₄-C₂₈ dicarboxylic acid or an anhydride or ester thereof,under thermal conditions, i.e., at temperatures of about 180° C. to 280°C. These conditions are similar to those used for preparing thermalprocess PIBSA. Optionally, this reaction takes place in the presence ofa strong acid, such as sulfonic acid. See for example U.S. Pat. No.6,156,850.

Optionally, a solvent may be used to dissolve the reactants. Thereaction solvent must be one which dissolves both the acidic reactantand the high molecular weight olefin. It is necessary to dissolve theacidic reactant and high molecular weight olefin so as to bring theminto intimate contact in the solution polymerization reaction. It hasbeen found that the solvent must also be one in which the resultantcopolymers are soluble.

Suitable solvents include liquid saturated or aromatic hydrocarbonshaving from 6 to 20 carbon atoms; ketones having from 3 to 5 carbonatoms; and liquid saturated aliphatic dihalogenated hydrocarbons havingfrom 1 to 5 carbon atoms per molecule, preferably from 1 to 3 carbonatoms per molecule. By “liquid” is meant liquid under the conditions ofpolymerization. In the dihalogenated hydrocarbons, the halogens arepreferably on adjacent carbon atoms. By “halogen” is meant F, Cl and Br.The amount of solvent must be such that it can dissolve the acidicreactant and high molecular weight olefin in addition to the resultingcopolymers. The volume ratio of solvent to high molecular weight olefinis suitably between 1:1 and 100:1 and is preferably between 1.5:1 and4:1.

Suitable solvents include the ketones having from 3 to 6 carbon atomsand the saturated dichlorinated hydrocarbons having from 1 to 5, morepreferably 1 to 3, carbon atoms.

Examples of suitable solvents include, but are not limited to:

-   1. ketones, such as: acetone; methylethylketone; diethylketone; and    methylisobutylketone;-   2. aromatic hydrocarbons, such as: benzene; xylene; and toluene;-   3. saturated dihalogenated hydrocarbons, such as: dichloromethane;    dibromomethane; 1-bromo-2-chloroethane; 1,1-dibromoethane;    1,1-dichloroethane; 1,2-dichloroethane; 1,3-dibromopropane;    1,2-dibromopropane; 1,2-dibromo-2-methylpropane;    1,2-dichloropropane; 1,1-dichloropropane; 1,3-dichloropropane;    1-bromo-2-chloropropane; 1,2-dichlorobutane; 1,5-dibromopentane; and    1,5-dichloropentane; or-   4. mixtures of the above, such as: benzenemethylethylketone.

The copolymer is conveniently separated from solvent and any unreactedacidic reactant by conventional procedures such as phase separation,solvent distillation, precipitation and the like. If desired, dispersingagents and/or co-solvents may be used during the reaction.

The polyisobutenyl succinic anhydride (PIBSA), which may be directlyadded to copolymer reactant (i) or (ii), is generally prepared by anumber of well-known processes including the method disclosed within.For example, there is a well-known thermal process (see, e.g., U.S. Pat.No. 3,361,673), an equally well-known chlorination process (see, e.g.,U.S. Pat. No. 3,172,892), a combination of the thermal and chlorinationprocesses (see, e.g., U.S. Pat. No. 3,912,764), catalytic strong acidprocesses (see, e.g., U.S. Pat. Nos. 3,819,660 and 6,156,850), and freeradical processes (see, e.g., U.S. Pat. Nos. 5,286,799 and 5,319,030).Such compositions include one-to-one monomeric adducts (see, e.g., U.S.Pat. Nos. 3,219,666 and 3,381,022), as well as high succinic ratioproducts, adducts having alkenyl-derived substituents adducted with atleast 1.3 succinic groups per alkenyl-derived substituent (see, e.g.,U.S. Pat. No. 4,234,435).

Polyalkylene succinic anhydrides also can be produced thermally alsofrom high methylvinylidene polybutene as disclosed in U.S. Pat. No.4,152,499. This process is further discussed in U.S. Pat. No. 5,241,003for the case where the succinic ratio is less than 1.3 and in EP 0 355895 for the case where the succinic ratio is greater than 1.3. EuropeanApplications EP 0 602 863 and EP 0 587 381, and U.S. Pat. No. 5,523,417disclose a procedure for washing out the polymaleic anhydride resin frompolyalkylene succinic anhydride prepared from high methylvinylidenepolybutene. A polyalkylene succinic anhydride with a succinic ratio of1.0 is disclosed. One advantage of polyalkylene succinic anhydride fromhigh methylvinylidene polybutene is that it can be prepared essentiallyfree of chlorine. U.S. Pat. No. 4,234,435 teaches a preferredpolyalkene-derived substituent group with a M_(n) in the range of1500-3200. For polybutenes, an especially preferred M_(n) range is1700-2400. This patent also teaches that the succinimides must have asuccinic ratio of at least 1.3. That is, there should be at least 1.3succinic groups per equivalent weight of polyalkene-derived substituentgroup. Most preferably, the succinic ratio should be from 1.5 to 2.5.

Other suitable alkenyl succinic anhydrides includes those described inU.S. Pat. No. 6,030,930. Typical alkenyl used in the preparation areethylene and 1-butene copolymers.

(B) The Ether Compounds

In one embodiment of the present invention, the copolymer is furtherreacted with an ether compound capable of linking two succinimidegroups. Suitable ether compounds include, but are not limited to, thefollowing:

Polyether Polyamines

Examples of suitable polyetheramines include compounds having thefollowing structure:

wherein R₁ is independently hydrogen or a hydrocarbyl group having 1 to4 carbons, and n is the degree of polymerization. Generally thepolyether polyamines suitable for use in the present invention willcontain at least about one ether unit, preferably from about 5 to about100, more preferably from about 10 to 50, and even more preferably fromabout 15 to about 25 ether units.

The polyether polyamines can be based on polymers derived from C₂-C₆epoxides such as ethylene oxide, propylene oxide, and butylene oxide.Examples of polyether polyamines are sold under the Jeffamine® brand andare commercially available from Hunstman Corporation located in Houston,Tex.

Other examples of suitable polyetheramines include polyoxytetramethylenepolyamine compounds having the following structure:

wherein n is the degree of polymerization (i.e., number of monomer etherunits).Polyether Amine Derivatives

Furthermore, the copolymer reactant may be reacted with a polyetheramino alcohol or amino thiol.

Polyether Amino Alcohol

Typically, amino alcohols may be formed when the alcohol end groups of acompound are not completely converted to amines during reactions, suchas reductive amination. Also, one may initiate a polymer chain (i.e.grow propylene or ethylene oxide) from an amino group and therefore havean amino on one end of the polymer chain (i.e. initiator) and an alcoholterminus, or an amine internally in the molecule with alcohol termini.

Examples of suitable polyetheramino alcohols include compounds havingthe following structure:

wherein R₁ is independently a hydrogen or hydrocarbyl group, having 1 to4 carbons, and n is the degree of polymerization. Generally, thepolyether amino alcohols, suitable for use in the present invention willcontain at least about one ether unit, preferably from about 5 to about100, more preferably from about 10 to about 50, and even more preferablyfrom about 15 to about 25 ether units.

Other examples of suitable polyetheramino alcohols includepolyoxytetramethyleneamino alcohol compounds having the followingstructure:

wherein n is the degree of polymerization.Polyether Amino Thiol

Examples of suitable polyetheramino thiols include compounds having thefollowing structure:

wherein R₁ is independently a hydrogen or hydrocarbyl group, having 1 to4 carbons and n is the degree of polymerization.

Other examples of suitable polyetheramino thiols includepolyoxytetramethyleneamino thiol having the following structure:

wherein n is the degree of polymerization.

Generally, the polyetheramino thiols suitable for use in the presentinvention will contain at least about one ether unit, preferably fromabout 5 to about 100, more preferably from about 10 to about 50, andeven more preferably from about 15 to about 25 ether units.

Ether Polyamines

Ether Diamines

In yet another embodiment of the present invention, the copolymer may bereacted with ether diamines. Suitable diamines are reacted with thecopolymer, such as decyloxypropyl-1,3-diaminopropane,isodecyloxypropyl-1,3-diaminopropane,isododecyloxypropyl-1,3-diaminopropane,dodecyl/tetradecyloxypropyl-1,3-diaminopropane,isotridecyloxypropyl-1,3-diaminopropane,tetradecyloxypropy-1,3-diaminopropane.

Polyether Polyol

In yet another embodiment of the present invention, the copolymer may bereacted with a polyether containing at least two hydroxyl end groups toform an ester. The polyether polyols have the following structure:

wherein R₁ is independently a hydrogen or hydrocarbyl group, having 1 to4 carbons, and n is the degree of polymerization.

Other examples of suitable polyether polyols includepolyoxytetramethylene polyol compounds, such as those referred to asTerathane® which may be purchased from DuPont Corporation, Wilmington,Del., having the following structure:

wherein n is the degree of polymerization.

Suitable polyether polyols include, but are not limited to, thefollowing: polyoxyethylene glycol, polyoxypropylene glycol,polyoxybutylene glycol, and polyoxytetramethylene glycol.

The molecular weight of the presently employed polyether polyol willgenerally range from about 150 to about 5000, preferably from about 500to about 2000.

Generally, the polyether compounds suitable for use in the presentinvention will contain at least one ether unit preferably from about 5to about 100, more preferably from about 10 to about 50, and even morepreferred from about 15 to about 25 ether units.

Generally, the polyether compounds suitable for use in the presentinvention may be derived from only one ether type or a mixture of ethertypes, such as poly(oxyethylene-co-oxypropylene) diamine. The mixture ofether units may be block, random, or alternating copolymers. Thepresently employed ether compounds are capable of reacting with at leasttwo carboxylic acid groups or anhydride derivatives thereof.

Generally, the copolymer may be reacted with a mixture of polyetherpolyamines, polyether amino alcohols, polyether amino thiols, polyetherpolyols, or ether diamines to form a mixture of imides, amides andesters.

(C) Amino Aromatic Reactant

In addition to the ether compound (i.e. polyether polyamine, polyetherpolyamine derivative, polyether polyol, ether dimaines and ethertriamine) above, the copolymer is also reacted with at least one aminoaromatic selected from the group consisting of (a)N-arylphenylenediamine, (b) aminocarbazole, (c) amino-indazolinone, (d)aminomercaptotriazole, (e) aminoperimidine; and (f) aryloxyphenyleneamine.

Preferred amino aromatic compounds are descriped as follows:

-   (a) an N-arylphenylenediamine represented by the formula:

-    in which R₁ is H, —NHaryl, —NHalkaryl, or a branched or straight    chain radical having from 4 to 24 carbon atoms that can be alkyl,    alkenyl, alkoxyl, aralkyl or alkaryl; R₂ is —NH₂,    —(NH(CH₂)—_(n))—_(m)NH₂, —NHalkyl, —NHaralkyl, —CH₂-aryl-NH₂, in    which n and m each have a value from 1 to 10; and R₃ is hydrogen,    alkyl, alkenyl, alkoxyl, aralkyl, or alkaryl, having from 4 to 24    carbon atoms. Particularly preferred N-arylphenylenediamines are    N-phenylphenylenediamines (NPPDA), for example,    N-phenyl-1,4-phenylenediamine, N-phenyl-1,3-phenylenediamine, and    N-phenyl-1,2-phenylenediamine and N-naphthyl-1,4-phenylenediamine.    Other polyamines of NPPDA may also be included, such as    N-aminopropyl-N′-phenylphenylenediamine.-   (b) aminocarbazole represented by the formula:

-    in which R and R¹ each independently represent hydrogen or an alkyl    or alkenyl radical having from 1 to 14 carbon atoms,-   (c) an amino-indazolinone represented by the formula:

-    in which R is hydrogen or an alkyl radical having from 1 to 14    carbon atoms; and-   (d) an aminomercaptotriazole represented by the formula:

-   (e) an aminoperimidine represented by the formula:

-    in which R represents hydrogen or an alkyl radical having from 1 to    14 carbon atoms; and-   (f) an aryloxyphenyleneamine represented by the formula:

-    in which R₁ is H, —NHaryl, —NHalkaryl, or ranched or straight chain    radical having from 4 to 24 carbon atoms that can be alkyl, alkenyl,    alkoxyl, aralkyl or alkaryl; R₂ is —NH₂, —(NH(CH₂)—_(n))—_(m)NH₂,    —NHalkyl, or —NHaralkyl, in which n and m each have a value from 1    to 10; and R₃ is hydrogen, alkyl, alkenyl, alkoxyl, aralkyl, or    alkaryl, having from 4 to 24 carbon atoms. A particularly preferred    aryloxyphenyleneamine is 4-phenoxyaniline.    Method of Making the Lubricating Oil Additive Composition

The lubricating oil additive composition is prepared by a processcomprising charging the reactant copolymer (e.g., at least one ofcopolymers (i), (ii) and (iii) as described herein) in a reactor,optionally under a nitrogen purge, and heating at a temperature of fromabout 80° C. to about 170° C. Optionally, a diluent oil may be chargedoptionally under a nitrogen purge in the same reactor. Both an aminoaromatic amine and a ether polyamine, polyetheramine, polyetheraminederivative and/or polyether polyol are charged, optionally under anitrogen purge, to the reactor. This mixture is heated under a nitrogenpurge to a temperature in range from about 130° C. to about 200° C.Optionally, a vacuum is applied to the mixture for about 0.5 to about2.0 hours to remove excess water.

The lubricating oil additive composition can also be made using aprocess comprising simultaneously charging all the reactants (reactantcopolymer (i), (ii), or (iii); the amino aromatic amine; and the ethercompound which consists of at least one of a polyether polyamine,polyether amino alcohol, polyetheramino thiol, ether polyamine andpolyether polyol) at the desired ratios into the reactor. One or more ofthe reactants can be charged at an elevated temperature to facilitatemixing and reaction. A static mixer can be used to facilitate mixing ofthe reactants as they are being charged to the reactor. The reaction iscarried out for about 0.5 to 2 hours at a temperature from about 130° C.to 200° C. Optionally a vacuum is applied to the reaction mixture duringthe reaction period.

Preferably, the ratio of polyetheramine, polyetheramine derivativeand/or polyetherpolyol to monoethylenically unsaturated C₃-C₂₈monocarboxylic acid or ester or C₄-C₂₈ dicarboxylic acid, anhydride orester is 0.45 to 0.05; more preferred, the ratio is 0.40 to 0.1; evenmore preferred, the ratio is 0.35 to 0.20; most preferred, the ratio is0.33.

Preferably, the ratio of amino aromatic compound to monoethylenicallyunsaturated C₃-C₂₈ monocarboxylic acid or ester thereof, or C₄-C₂₈dicarboxylic acid, anhydride or ester is 0.95 to 0.10; more preferred,the ratio is 0.40 to 0.20; even more preferred, the ratio is 0.35 to0.25; most preferred, the ratio is 0.33.

In one embodiment of the invention, the non-free radical catalyzedreaction product of compound (i)(a) and compound (i)(b) or (i)(c), whichis contacted with either copolymer (i) or copolymer (ii) or both, may becontacted in the presence of component (C) (i.e. the aromatic amine)prior to the addition of component (B) (i.e. the ether compound).

Lubricating Oil Composition

The lubricating oil additive composition described above is generallyadded to a base oil that is sufficient to lubricate moving parts, forexample internal combustion engines, gears, and transmissions.Typically, the lubricating oil composition of the present inventioncomprises a major amount of oil of lubricating viscosity and a minoramount of the lubricating oil additive composition.

The base oil employed may be any of a wide variety of oils oflubricating viscosity. The base oil of lubricating viscosity used insuch compositions may be mineral oils or synthetic oils. A base oilhaving a viscosity of at least 2.5 cSt at 40° C. and a pour point below20° C., preferably at or below 0° C., is desirable. The base oils may bederived from synthetic or natural sources. Mineral oils for use as thebase oil in this invention include, for example, paraffinic, naphthenicand other oils that are ordinarily used in lubricating oil compositions.Synthetic oils include, for example, both hydrocarbon synthetic oils andsynthetic esters and mixtures thereof having the desired viscosity.

Hydrocarbon synthetic oils may include, for example, oils prepared fromthe polymerization of ethylene, polyalphaolefin or PAO oils, or oilsprepared from hydrocarbon synthesis procedures using carbon monoxide andhydrogen gases such as in a Fisher-Tropsch process. Useful synthetichydrocarbon oils include liquid polymers of alpha olefins having theproper viscosity. Especially useful are the hydrogenated liquidoligomers of C₆ to C₁₂ alpha olefins such as 1-decene trimer. Likewise,alkyl benzenes of proper viscosity, such as didodecyl benzene, can beused. Useful synthetic esters include the esters of monocarboxylic acidsand polycarboxylic acids, as well as mono-hydroxy alkanols and polyols.Typical examples are didodecyl adipate, pentaerythritol tetracaproate,di-2-ethylhexyl adipate, dilaurylsebacate, and the like. Complex estersprepared from mixtures of mono and dicarboxylic acids and mono anddihydroxy alkanols can also be used. Blends of mineral oils withsynthetic oils are also useful.

Thus, the base oil can be a refined paraffin type base oil, a refinednaphthenic base oil, or a synthetic hydrocarbon or non-hydrocarbon oilof lubricating viscosity. The base oil can also be a mixture of mineraland synthetic oils.

Method of Use of the Present Invention

The lubricating oil additive composition of the present invention isadded to an oil of lubricating viscosity thereby producing a lubricatingoil composition. The lubricating oil composition contacts the engine,improving dispersancy. Accordingly, the present invention is alsodirected to a method of improving dispersancy in an internal combustionengine which comprises operating the engine with the lubricating oilcomposition of the invention.

The following examples are presented to illustrate specific embodimentsof this invention and are not to be construed in any way as limiting thescope of the invention.

EXAMPLES Example 1 Preparation of Terpolymer (Copolymer (i))

2513 grams of high methylvinylidene polyisobutylene having a numberaverage molecular weight (Mn) of about 2300 and a methylvinylidenecontent of about 78% (which is available from BASF as Glissopal® 2300)was charged to a 4-L reactor equipped with agitator, temperaturecontroller and overhead condenser and receiver. 27.3 grams 1-hexadecenewas also charged to the reactor, and the agitated mixture was heated to150° C. Traces of moisture were removed by sparging 250 scm³/minnitrogen through the mixture for about an hour. After drying, thenitrogen was fed to the reactor head space at a rate of 30 scm³/min.178.8 grams maleic anhydride and 16.4 grams dicumyl peroxide in a 50%solution with toluene were fed simultaneously to the reactor over 2hours. After the maleic anhydride and dicumyl peroxide charging werefinished, the temperature of the reactor was maintained at 150° C. foranother 1.5 hours. The reactor was heated to 190° C. During the heatingof the reactor, the pressure was gradually lowered to 20 mm Hg when thetemperature of the reactor reached 180° C. The temperature was held at190° C. and the pressure was held at 20 mm Hg for 1 hour during which 15grams of condensate was collected. The product was cooled and a yield of2693 grams of copolymer (i) was obtained.

Example 2 Terpolymer Preparation with Post Treatment Step (Copolymer(iii))

67,584 grams of high methylvinylidene polyisobutylene having a numberaverage molecular weight (M_(n)) of about 2300 and a methylvinylidenecontent of about 78% (which is available from BASF as Glissopal® 2300)was charged to a 30-gallon reactor equipped with agitator, temperaturecontroller and overhead condenser and receiver. 733 grams 1-hexadecenewas also charged to the reactor, and the agitated mixture was heated to150° C. Traces of moisture were removed by sparging 6.7 sL/min nitrogenthrough the mixture for about an hour. After drying, the nitrogen wasfed to the reactor head space at a rate of 500 scm³/min. 4802 gramsmaleic anhydride and 441 grams of melted dicumyl peroxide were fedsimultaneously to the reactor over 2 hours. After the maleic anhydrideand dicumyl peroxide charging were finished, the temperature of thereactor was maintained at 150° C. for another 1.5 hours. The resultingterpolymer was then post-treated by heating from 150° C. to about 232°C. When the temperature reached about 170° C., 68.3 grams of sulfonicacid (derived from a sulfonation of a mixture of alkyl benzenes) wascharged to the reactor and heating was continued until the reactortemperature reached about 232° C. Immediately after charging thesulfonic acid, 3201 grams maleic anhydride was fed to the reactor overabout 1 hour. The pressure control was set to hold at 10.3 psig. Thereactor temperature was held at about 232° C. and 10.3 psig for 2 hours.The reaction product was cooled to a temperature below 190° C. and thendiluted with 46,600 grams of 100 Neutral oil. This yielded about 119,500grams of oil-diluted copolymer (iii). Small amounts of sediment wereremoved using a pressure filter and diatomaceous earth such as Celite®512.

Example 3 Preparation of Oil Soluble Lubricating Oil Additive

300 grams of polymer prepared according to Example 2 were charged to areactor under a nitrogen purge and heated to a temperature of 140° C.The charged polymer was put under a vacuum for 45-60 minutes. In thesame reactor, 22.5 grams of diluent oil was charged. In the samereactor, 17.72 grams of N-phenyphenylenediamine (N-PPDA) was chargedunder a nitrogen purge. 4.76 grams of polypropyleneoxide diamine (PPODA, having an approximate number average molecular weight of 400) wasslowly charged to the same reactor under a nitrogen purge. The reactoris heated to 150° C. under a nitrogen purge. The reactor is put under avacuum for 1.5 hours to remove water. The charge mole ratio of N-PPDA toanhydride was 0.8. The charge mole ratio of PPO DA to anhydride was0.10.

Following the general procedure of Example 3, Examples 4-7 andComparative Examples E-F were carried out and are also summarized inTable 1 and Table 1A.

TABLE 1 Post Treated Terpolymer reacted with NPPDA or 4-PA andpolyoxyalkylene diamine CMR CMR Polymer Amine 1 Amine 1 Amine 2 Amine 2Charge Amine 1 Charge Anhydride Charge Anhydride Example (g) Type (g)Content Amine 2 Type (g) Content 3 300 NPPDA 17.72 0.80 PPO DA 400 g/mol4.76 0.10 4 300 NPPDA 8.84 0.40 PPO DA 400 g/mol 14.4 0.30 5 75 NPPDA1.29 0.23 PTMO DA 1000 g/mol 11.5 0.38 6 100 NPPDA 1.70 0.23 PEO DA 2000g/mol 30.8 0.38 7 100 4-PA 4.0 0.55 PPO DA 4000 g/mol 36.0 0.23 NPPDA:N-phenylphenylenediamine PPO DA: Polypropylene oxide diamine PEO DA:Polyethylene oxide diamine PTMO DA: Polytetramethyleneoxide diamine4-PA: 4-phenoxyaniline

TABLE 1A Comparative Examples: Post Treated Terpolymer reacted withpolyoxyalkylene diamine CMR CMR Polymer Amine 1 Amine 1 Amine 2 Amine 2Charge Amine 1 Charge Anhydride Charge Anhydride Example (g) Type (g)Content Amine 2 Type (g) Content E 100 none None N/A PEO DA 1100 g/mol28.40 0.5 F 80 none None N/A PEO DA 2000 g/mol 37.87 0.5 NPPDA:N-phenylphenylenediamine PPO DA: Polypropylene oxide diamine PEO DA:Polyethylene oxide diamine

Example 8 Preparation of Oil Soluble Lubricating Oil Additive

88 grams of polymer prepared according to Example 1 were charged to areactor under a nitrogen purge and heated to a temperature of 140° C.The charged polymer was put under a vacuum for 45-60 minutes. In thesame reactor, 72.46 grams of diluent oil was charged. In the samereactor, 2.46 grams of N-phenyphenylenediamine (N-PPDA) was chargedunder a nitrogen purge. 26.04 grams of polyethyleneoxide diamine (PEODA, having an approximate number average molecular weight of 1000) wasslowly charged to the same reactor under a nitrogen purge. The reactoris heated to 150° C. under a nitrogen purge. The reactor is put under avacuum for 1.5 hours to removes excess water. The charge mole ratio ofN-PPDA to anhydride was 0.23. The charge mole ratio of PEO DA toanhydride was 0.39.

Following the general procedure of Example 8, Example 9 and ComparativeExamples A-D were carried out and are also summarized in Table 2 andTable 2A.

TABLE 2 Terpolymer (no post treatment) reacted with NPPDA andpolyoxyalkylene diamine CMR CMR Polymer Amine 1 Amine 1 Amine 2 Amine 2Charge Amine 1 Charge Anhydride Charge Anhydride Example (g) Type (g)Content Amine 2 Type (g) Content 8 88 NPPDA 2.46 0.23 PEO DA 1000 g/mol26.04 0.39 9 105 NPPDA 4.24 0.33 PEO DA 500 g/mol 12.14 0.33 PEO DA:Polyethylene oxide diamine

TABLE 2A Comparative Examples: Terpolymer (no post treatment) reactedwith polyoxyalkylene diamine CMR CMR Polymer Amine 1 Amine 1 Amine 2Amine 2 Charge Amine 1 Charge Anhydride charge Anhydride Example (g)Type (g) Content Amine 2 Type (g) Content A 90 none none N/A PEO DA 900g/mol 27.89 0.5 B 100 none none N/A PEO DA 400 g/mol 17.13 0.5 C 75 nonenone N/A PEO DA 1100 g/mol 29.62 0.5 D 60 none none N/A PEO DA 2000g/mol 39.49 0.5 PEO DA: Polyethylene oxide diamine

Example 10 PolyPIBSA Preparation with Post Treatment Step (Copolymer(iii))

52,178 grams of high methylvinylidene polyisobutylene having a numberaverage molecular weight (M_(n)) of about 2300 and a methylvinylidenecontent of about 78% (which is available from BASF as Glissopal® 2300)was charged to a 30-gallon reactor equipped with agitator, temperaturecontroller and overhead condenser and receiver. 14,267 grams of a highmethylvinylidene polyisobutylene having a number average molecularweight (M_(n)) of about 1000 and a methylvinylidene content of about 82%(which is available from BASF as Glissopal® 1000) was charged to thereactor and the agitated mixture was heated to 150° C. This produced a66,445 gram blend of high methylvinylidene polyisobutylene having anumber average molecular weight of about 1800. Traces of moisture wereremoved by sparging 6.7 sL/min nitrogen through the mixture at 150° C.for about an hour. After drying, the nitrogen was fed to the reactorhead space at a rate of 500 scm³/min.reactor. 5426 grams maleicanhydride and 499 grams of melted dicumyl peroxide were fed to thereactor simultaneously over 2 hours. After the maleic anhydride anddicumyl peroxide charging were finished, the temperature of the reactorwas maintained at 150° C. for another 1.5 hours. The resulting polyPIBSAwas then post-treated by heating from 150° C. to about 232° C. When thetemperature reached about 170° C., 66.7 grams of sulfonic acid (derivedfrom a sulfonation of a mixture of alkyl benzenes) was charged to thereactor and heating was continued until the reactor temperature reachedabout 232° C. Immediately after charging the sulfonic acid, 3617 gramsof maleic anhydride was fed to the reactor over about 1 hour. Thepressure control was set to hold at 10.3 psig. The reactor temperaturewas held at about 232° C. and 10.3 psig for 2 hours. The reactionproduct was cooled to a temperature below 190° C. and then diluted with46,200 grams of 100 Neutral oil. This yielded about 118,400 grams ofoil-diluted polyPIBSA. Small amounts of sediment were removed using apressure filter and diatomaceous earth such as Celite® 512.

Example 11 Preparation of Oil Soluble Lubricating Oil Additive

100 grams of polymer prepared according to Example 10 were charged to areactor under a nitrogen purge and heated to a temperature of 140° C.The charged polymer was put under a vacuum for 45-60 minutes. In thesame reactor, 66.4 grams of diluent oil was charged. In the samereactor, 1.79 grams of N-phenyphenylenediamine (N-PPDA) was chargedunder a nitrogen purge. 64.6 grams of polypropyleneoxide diamine (PPODA, having an approximate number average molecular weight of 4000 g/mol)was slowly charged to the same reactor under a nitrogen purge. Thereactor is heated to 150° C. under a nitrogen purge. The reactor is putunder a vacuum for 1.5 hours to remove water. The charge mole ratio ofN-PPDA to anhydride was 0.23. The charge mole ratio of PEO DA toanhydride was 0.38.

Following the general procedure of Example 11, Examples 12-14 andComparative Examples G-H were carried out and are also summarized inTable 3 and Table 3A.

TABLE 3 Post-treated PolyPIBSA polymer reacted with NPPDA andpolyoxyalkylene diamine CMR CMR Polymer Amine 1 Amine 1 Amine 2 Amine 2Charge Amine 1 Charge Anhydride Charge Anhydride Example (g) Type (g)Content Amine 2 Type (g) Content 11 100 NPPDA 1.79 0.23 PPO DA 4000g/mol 64.6 0.38 12 75 NPPDA 1.29 0.22 PTMO DA 1000 g/mol 12.5 0.39 13 75NPPDA 1.29 0.22 PEO DA 1000 g/mol 12.5 0.39 14 100 NPPDA 1.79 0.23 PPODA 400 g/mol 6.46 0.38 NPPDA: N-phenylphenylenediamine PEO DA:Polyethylene oxide diamine PPO DA: Polypropylene oxide diamine PTMO DA:Polytetramethyleneoxide diamine

TABLE 3A Post-treated PolyPIBSA polymer reacted with polyoxyalkylenediamine CMR CMR Polymer Amine 1 Amine 1 Amine 2 Amine 2 Charge Amine 1Charge Anhydride Charge Anhydride Example (g) Type (g) Content Amine 2Type (g) Content G 105 none none N/A PEO DA 1100 g/mol 32.06 0.5 H 85none none N/A PEO DA 2000 g/mol 41.46 0.5 PEO DA: Polyethylene oxidediamine

Example 15 Preparation of PolyPIBSA (Copolymer (ii))

4005 grams of high methylvinylidene polyisobutene having a numberaverage molecular weight (M_(n)) of about 1000 and a methylvinylidenecontent of about 76% (which is commercially available from BASF and isknown as Glissopal 1000) was charged to a reactor and the reactor washeated to a temperature of about 150° C. 589 grams maleic anhydride and54.14 grams of dicumyl peroxide were fed to the reactor. The temperatureof the reactor was maintained at 150° C. for 1.0 hour after the maleicanhydride and dicumyl peroxide are charged to the reactor. The reactorwas heated to about 200° C. over a period of about 1.0 hour, after whicha vacuum was applied to reduce the pressure to 0 psia while maintainingthe temperature at 200° C. The reactor was held under vacuum pressurefor about 1.5 hours at 200° C. The reactor pressure was then increasedto ambient conditions and the product was then filtered to provide theneat product.

Example 16 Preparation of Oil Soluble Lubricating Oil Additive

75 grams of polymer prepared according to Example 15 were charged to areactor under a nitrogen purge and heated to a temperature of 140° C.The charged polymer was put under a vacuum for 45-60 minutes. In thesame reactor, 60.7 grams of diluent oil was charged. In the samereactor, 3.40 grams of N-phenyphenylenediamine (N-PPDA) was chargedunder a nitrogen purge. 12.3 grams of polypropyleneoxide diamine (PPODA, having an approximate number average molecular weight of 400) wasslowly charged to the same reactor under a nitrogen purge. The reactorwas heated to 150° C. under a nitrogen purge. The reactor was put undera vacuum for 1.5 hours to removes excess water. The charge mole ratio ofN-PPDA to anhydride was 0.23. The charge mole ratio of PEO DA toanhydride was 0.38.

Following the general procedure of Example 16, Examples 17 and 18 werecarried out and are also summarized in Table 4.

TABLE 4 Post-treated PolyPIBSA polymer reacted with NPPDA andpolyoxyalkylene diamine CMR CMR Polymer Amine 1 Amine 1 Amine 2 Amine 2charge Amine 1 charge Anhydride charge Anhydride Example (g) Type (g)Content Amine 2 Type (g) Content 16 75 NPPDA 3.40 0.23 PPO DA 400 g/mol12.3 0.38 17 75 NPPDA 11.79 0.80 PEO DA 2000 g/mol 16.0 0.10 18 75 NPPDA11.05 0.75 PPO DA 2000 g/mol 20.0 0.125 NPPDA: N-phenylphenylenediaminePEO DA: Polyethylene oxide diamine PPO DA: Polypropylene oxide diamine

Examples A-H are comparative examples, which are compared to Examples3-9, 11-14 and 16-18 of the present invention. The comparative exampleswere prepared by reacting one of the copolymers employed in the presentinvention with a polyoxyalkylene diamine and without an aromatic amine.The product of Comparative Examples A and B exhibited haze, whendissolved in a lubricating oil, which is considered an undesirablequality in a dispersant. The remaining Comparative Examples C-H formedan insoluble gel when dissolved in a lubricating oil, which is alsoconsidered an undesirable quality in a dispersant.

By comparison Examples 3-9, 11-14 and 16-18 in which the copolymer wasreacted with both a polyoxyalkene diamine and an aromatic amine,exhibited little haze and did not form a gel. The resulting products ofthe examples of the invention are soluble in an oil of lubricatingviscosity.

Example 19 Preparation of Low Molecular Weight PIB/Maleic AnhydrideCopolymer (Copolymer (ii))

3004.7 grams of polyisobutylene having a number average molecular weight(M_(n)) of about 350 and a methylvinylidene content of about 78% (whichis available from Texas Petroleum Company as TPC-535) was charged to a10-reactor equipped with agitator, temperature controller, and overheadcondenser and receiver. Traces of moisture were removed by heating to153° C. under nitrogen for about 45 minutes. 715 grams maleic anhydrideand 27.86 grams dicumyl peroxide in a 50% solution with xylene were fedsimultaneously to the reactor over 297 minutes. After the maleicanhydride and dicumyl peroxide charging was finished, the temperature ofthe reactor was maintained at 153° C. for another 30 minutes. Thereactor was heated to a temperature of about 190° C. for approximately 1hour after which a vacuum was applied to reduce the pressure to 0 psiawhile maintaining the temperature at approximately 190° C. The reactorwas held under vacuum pressure for about 1 hour at 190° C. The reactorpressure was then increased to ambient conditions and the product wasfiltered to provide the heat product.

Example 20

84.2 grams of polymer prepared according to Example 19, 56.8 grams baseoil, and 17.39 grams N-phenylenephenylendiamine were charged to a 1000mL glass reactor. A nitrogen sweep was introduced to the reactor. Thereactor was heated from a temperature of 19° C. to a temperature of 160°C. and the contents were stirred. To the reactor, 450.0 grams PIBSA(based on polyisobutene having a number average molecular weight of 2300and made according to the process described in U.S. Pat. No. 6,156,850)was charged to the reactor. To the reactor, 57.36 grams of polyethyleneoxide diamine (PEO DA, having an approximate number average molecularweight of 600 and which may be purchased from Hunstman Corporation,Houston, Tex., having the trade name Jeffamine® ED-series). A vacuum wasapplied to the reactor. The viscosity of the resulting reaction productwas 259.3 cSt at 100° C.

Following the general procedure of Example 20, Examples 21-22 werecarried out and are summarized in Table 5.

TABLE 5 PIB/Maleic Anhydride Copolymer reacted with NPPDA andpolyoxyalkylene diamine CMR CMR Polymer Amine 1 Amine 1 Amine 2 Amine 2Charge Amine 1 Charge Anhydride Amine 2 Charge Anhydride ViscositycStExample (g) Type (g) Content Type (g) Content @ 100° C. 20 84.2 NPPDA17.39 PEO DA 57.36 259.3 600 g/mol 21 126.3 NPPDA 10.9 TEGD 22.17 164.222 156.4 NPPDA 12.42 TEGD 25.34 124.7 NPPDA: N-phenylphenylenediaminePEO DA: polyoxyethylene diamine TEGD: triethylene glycol diamine

Example 23

Examples 5, 11 and 20, which exemplify the lubricating oil additivecomposition of the present invention, were evaluated for percentviscosity increase using a soot thickening bench test, which measuresthe ability of the formulation to disperse and control viscosityincrease resulting from the addition of carbon black, a soot surrogate.Using the soot thickening bench test, the viscosity of a fresh oil ismeasured in centistokes. The fresh oil is then treated with 10 wt %Raven 1040 carbon black, supplied by Columbia Chemical Co., to form amixture containing approximately 5 grams Raven 1040 carbon black and 45grams fresh oil (test oil). The test oil, which contains carbon black,is then homogenized using a high speed tissue homogenizer for 60-75seconds to thoroughly mix the carbon black with the fresh oil. Theresulting test oil containing carbon black is then degassed at 100° C.for 30 minutes. The viscosity of the oil containing carbon black ismeasured according to methods that are well known in the art. Thepercent viscosity increase is calculated according to the followingformula:% viscosity increase=[(vis_(cbo)−vis_(fo))/(vis_(fo))×100]

-   -   vis_(cbo): viscosity of carbon black in oil    -   vis_(fo): viscosity of fresh oil

Using the soot thickening bench test, the percent viscosity increasecalculated for the additive composition of for Examples 5, 11, and 20 ina formulated oil was compared to a formulated oil that does not containthe lubricating oil additive composition of the present invention. Thefollowing additives were blended to make an additive package: 0.8 wt %of a metal corrosion inhibitor and an oxidation inhibitor package, 0.2wt % friction modifier, 0.2 wt % pour point depressant, 83.0 millimolesof a calcium based detergent package containing a phenate and asulfonate, 22.0 millimoles zinc dithiophosphate, 5.0 parts per millionfoam inhibitor, and 6.6 wt % viscosity index improver. This blendedadditive package was added to a mixture of basestocks which consists of67.0 wt % EHC60 oil, 9.0 wt % Exxon150N oil, and 24 wt % Exxon600N oil(all of which may be purchased from ExxonMobil Corporation, Fairfax,Va.) to provide the comparative oil formulation. To prepare theformulated lubricating oil composition of the present invention,approximately 7.2 wt % of the additive composition of Examples 5, 11,and 20 was top treated to the formulated comparison oil.

The results of the soot thickening bench test are summarized in Table 6.

TABLE 6 Soot Thickening Bench Test Results % Viscosity Example IncreaseSample Description 5 57.5 Post Treated Terpolymer reacted with NPPDA andpolyoxyalkylene diamine 11 283.4 Post-treated PolyPIBSA polymer reactedwith NPPDA and polyoxyalkylene diamine 20 44.0 PIB/Maleic AnhydrideCopolymer reacted with NPPDA and polyoxyalkylene diamineComparison >350.0 No copolymer/NPPDA/ (too viscose polyoxyalkylenediamine to measure) dispersant additive.

The results of the soot thickening bench test indicate that the percentviscosity increase using the lubricating oil additive composition of thepresent invention was lower than the percent viscosity increase in aformulated oil that does not contain the lubricating oil additivecomposition of the present invention, which was too viscous to measuresince the test employed only measures percent viscosity increase up to350%. This test indicates that the lubricating oil additive compositionof the present invention has good dispersant properties.

It is understood that although modifications and variations of theinvention can be made without departing from the spirit and scopethereof, only such limitations should be imposed as are indicated in theappended claims.

1. An oil-soluble lubricating oil additive composition prepared by theprocess which comprises reacting (A) at least one of the followingcopolymers: (i) a copolymer obtained by free radical copolymerization ofcomponents comprising: (a) at least one monoethylenically unsaturatedC₃-C₂₈ monocarboxylic acid or ester thereof, or C₄-C₂₈ dicarboxylicacid, anhydride or ester thereof; (b) at least one 1-olefin comprisingabout 2 to 40 carbon atoms or at least one polyolefin comprising about 4to 360 carbon atoms and having a terminal copolymerizable group in theform of a vinyl, vinylidene or alkyl vinylidene group or mixturesthereof; and (c) at least one monoolefin compound which iscopolymerizable with the monomers of (a) and (b) and is selected fromthe group consisting of: (1) an alkyl vinyl ether and an allyl alkylether where the alkyl group is hydroxyl, amino, dialkylamino or alkoxysubstituted or is unsubstituted, and containing 1 to 40 carbon atoms;(2) an alkyl amine and an N-alkylamide of a monoethylenicallyunsaturated mono- or dicarboxylic acid of 3 to 10 carbon atoms where thealkyl substituent contains 1 to 40 carbon atoms; (3) anN-vinylcarboxamide of carboxylic acids of 1 to 8 carbon atoms; (4) anN-vinyl substituted nitrogen-containing heterocyclic compound; and (5)at least one 1-olefin comprising about 2 to 40 carbon atoms or at leastone polyolefin comprising about 4 to about 360 carbon atoms and having aterminal copolymerizable group in the form of a vinyl, vinylidene oralkyl vinylidene group or mixtures thereof, provided that the olefinemployed is not the same as the olefin employed in (i)(b); (ii) acopolymer obtained by reacting compound (i)(a) and compound (i)(b) inthe presence of a free radical initiator; or (iii) a copolymer obtainedby (a) reacting compound (i)(a) with compound (i)(b) or (i)(c) in anon-free radical catalyzed reaction in the presence of copolymer (i) orcopolymer (ii) or both; or by (b) contacting copolymer (i) or copolymer(ii) or both with the non-free radical catalyzed reaction product ofcompound (i)(a) and compound (i)(b) or (i)(c); with (B) at least oneether compound selected from the group consisting of an ether polyamine,a polyether polyamine, a polyether amino alcohol, a polyether aminothiol, and a polyether polyol; and (C) at least one aromatic amine. 2.The lubricating oil additive composition of claim 1, wherein incopolymer (iii)(b), said copolymer (i) or copolymer (ii) or both arecontacted with the non-free radical catalyzed reaction product ofcompound (i)(a) and compound (i)(b) or (i)(c) in the presence ofcomponent (C).
 3. The lubricating oil additive composition of claim 1,wherein the ether compound (B) is a polyether polyamine.
 4. Thelubricating oil additive composition of claim 3, wherein the polyetherpolyamine is a polyoxyalkylene diamine wherein each alkylene unitindividually contains from 2 to 5 carbon atoms.
 5. The lubricating oiladditive composition of claim 4 wherein the oxyalkylene moiety isoxyethylene or oxypropylene, or mixtures thereof.
 6. The lubricating oiladditive composition of claim 5 wherein the polyether polyamine ispolyoxyethylene diamine.
 7. The lubricating oil additive composition ofclaim 1 wherein the copolymer is copolymer (i).
 8. The lubricating oiladditive composition of claim 1 wherein the copolymer is copolymer (ii).9. The lubricating oil additive composition of claim 8 wherein copolymer(ii) is polyPIBSA, obtained by the free radical catalyzed reaction ofmaleic anhydride and polyisobutylene.
 10. The lubricating oil additivecomposition of claim 1 wherein the copolymer is copolymer (iii).
 11. Thelubricating oil additive composition of claim 1 wherein the aromaticamine is selected from a group consisting of N-arylphenylenediamine,aminocarbazole, amino-indazolinone, aminomercaptotriazole,aminoperimidine, and aryloxyphenyleneamine.
 12. The lubricating oiladditive composition of claim 11 wherein the aromatic amine isN-arylphenylenediamine.
 13. The lubricating oil additive composition ofclaim 12 wherein the N-arylphenylenediamine is N-phenylphenylenediamine.14. The lubricating oil additive composition of claim 1 wherein compound(i)(b) of copolymer (i) is polyisobutene having a number averagemolecular weight (Me) of about
 2300. 15. The lubricating oil additivecomposition of claim 1 wherein (i)(a) is a dicarboxylic acid, anhydrideor ester thereof.
 16. The lubricating oil additive composition of claim15 wherein (i)(a) is maleic anhydride or ester thereof.
 17. Thelubricating oil additive composition of claim 1 wherein the monoolefinof (i)(c) is a 1-olefin.
 18. A lubricating oil composition comprising amajor amount of an oil of lubricating viscosity and a minor amount ofthe lubricating oil additive composition prepared by the process whichcomprises reacting (A) at least one of the following copolymers: (i) acopolymer obtained by free radical copolymerization of componentscomprising: (a) at least one monoethylenically unsaturated C₃-C₂₈monocarboxylic acid or ester thereof, or a C₄-C₂₈ dicarboxylic acid,anhydride or ester thereof (b) at least one 1-olefin comprising about 2to 40 carbon atoms or at least one polyolefin comprising about 4 to 360carbon atoms and having a terminal copolymerizable group in the form ofa vinyl, vinylidene or alkyl vinylidene group or mixtures thereof, and(c) at least one monoolefin compound which is copolymerizable with themonomers of (a) and (b) and is selected from the group consisting of:(1) an alkyl vinyl ether and an allyl alkyl ether where the alkyl groupis hydroxyl, amino, dialkylamino or alkoxy substituted or isunsubstituted, and containing 1 to 40 carbon atoms; (2) an alkyl amineand an N-alkylamide of a monoethylenically unsaturated mono- ordicarboxylic acid of 3 to 10 carbon atoms where the alkyl substituentcontains 1 to 40 carbon atoms; (3) an N-vinylcarboxamide of carboxylicacids of 1 to 8 carbon atoms; (4) an N-vinyl substitutednitrogen-containing heterocyclic compound; and (5) at least one 1-olefincomprising about 2 to 40 carbon atoms or at least one polyolefincomprising about 4 to about 360 carbon atoms and having a terminalcopolymerizable group in the form of a vinyl, vinylidene or alkylvinylidene group or mixtures thereof, provided that the olefin employedis not the same as the olefin employed in (i)(b); (ii) a copolymerobtained by reacting compound (i)(a) and compound (i)(b) in the presenceof a free radical initiator; (iii) a copolymer obtained by (a) reactingcompound (i)(a) with compound (i)(b) or (i)(c) in a non-free radicalcatalyzed reaction in the presence of copolymer (i) or copolymer (ii) orboth; or by (b) contacting copolymer (i) or copolymer (ii) or both withthe non-free radical catalyzed reaction product of compound (i)(a) andcompound (i)(b) or (i)(c); with (B) at least one ether compound selectedfrom the group consisting of an ether polyamine, a polyether polyamine,a polyether amino alcohol, a polyether amino thiol, and a polyetherpolyol; and (C) at least one aromatic amine.
 19. The lubricating oiladditive composition of claim 18, wherein in copolymer (iii)(b), saidcopolymer (i) or copolymer (ii) or both are contacted with the non-freeradical catalyzed reaction product of compound (i)(a) and compound(i)(b) or (i)(c) in the presence of component (C).
 20. The lubricatingoil composition of claim 18, wherein the ether compound (B) is apolyether polyamine.
 21. The lubricating oil composition of claim 20,wherein the polyether polyamine is a polyoxyalkylene diamine whereineach alkylene unit individually contains from 2 to 5 carbon atoms. 22.The lubricating oil composition of claim 21 wherein the oxyalkylenemoiety is oxyethylene or oxypropylene, or mixtures thereof.
 23. Thelubricating oil composition of claim 22 wherein the polyether polyamineis polyoxyethylene diamine.
 24. The lubricating oil composition of claim18 wherein the copolymer is copolymer (i).
 25. The lubricating oilcomposition of claim 18 wherein the copolymer is copolymer (ii).
 26. Thelubricating oil composition of claim 25 wherein copolymer (ii) ispolyPIBSA, obtained by the free radical catalyzed reaction of maleicanhydride and polyisobutylene.
 27. The lubricating oil composition ofclaim 18 wherein the copolymer is copolymer (iii).
 28. The lubricatingoil composition of claim 18 wherein the aromatic amine is selected froma group consisting of N-arylphenylenediamine, aminocarbazole,aminoindazolinone, aminomercaptotriazole, aminoperimidine, andaryloxyphenyleneamine.
 29. The lubricating oil composition of claim 28wherein the aromatic amine is N-arylphenylenediamine.
 30. Thelubricating oil composition of claim 29 wherein theN-arylphenylenediamine is N-phenylphenylenediamine.
 31. The lubricatingoil composition of claim 18 wherein compound (i)(b) of copolymer (i) ispolyisobutene having a number average molecular weight (Ma) of about2300.
 32. The lubricating oil composition of claim 31 wherein (i)(a) isa dicarboxylic acid, anhydride or ester thereof.
 33. The lubricating oilcomposition of claim 18 wherein (i)(a) is maleic anhydride or esterthereof.
 34. The lubricating oil composition of claim 1 wherein themonoolefin of (i)(c) is a 1-olefin.
 35. A method of making a lubricatingoil additive composition comprises reacting (A) at least one of thefollowing copolymers: (i) a copolymer obtained by free radicalcopolymerization of components comprising: (a) at least onemonoethylenically unsaturated C₃-C₂₈ monocarboxylic acid or esterthereof, or a C₄-C₂₈ dicarboxylic acid, anhydride or ester thereof (b)at least one 1-olefin comprising about 2 to 40 carbon atoms or at leastone polyolefin comprising about 4 to 360 carbon atoms and having aterminal copolymerizable group in the form of a vinyl, vinylidene oralkyl vinylidene group or mixtures thereof and (c) at least onemonoolefin compound which is copolymerizable with the monomers of (a)and (b) and is selected from the group consisting of: (1) an alkyl vinylether and an allyl alkyl ether where the alkyl group is hydroxyl, amino,dialkylamino or alkoxy substituted or is unsubstituted, and containing 1to 40 carbon atoms; (2) an alkyl amine and an N-alkylamide of amonoethylenically unsaturated mono- or dicarboxylic acid of 3 to 10carbon atoms where the alkyl substituent contains 1 to 40 carbon atoms;(3) an N-vinylcarboxamide of carboxylic acids of 1 to 8 carbon atoms;(4) an N-vinyl substituted nitrogen-containing heterocyclic compound;and (5) at least one 1-olefin comprising about 2 to 40 carbon atoms orat least one polyolefin comprising about 4 to about 360 carbon atoms andhaving a terminal copolymerizable group in the form of a vinyl,vinylidene or alkyl vinylidene group or mixtures thereof, provided thatthe olefin employed is not the same as the olefin employed in (i)(b);(iii) a copolymer obtained by reacting compound (i)(a) and compound(i)(b) in the presence of a free radical initiator; (iii) a copolymerobtained by (a) reacting compound (i)(a) with compound (i)(b) or (i)(c)in a non-free radical catalyzed reaction in the presence of copolymer(i) or copolymer (ii) or both; or by (b) contacting copolymer (i) orcopolymer (ii) or both with the non-free radical catalyzed reactionproduct of compound (i)(a) and compound (i)(b) or (i)(c); with (B) atleast one ether compound selected from the group consisting of an etherpolyamine, a polyether polyamine, a polyether amino alcohol, a polyetheramino thiol, and a polyether polyol; and (C) at least one aromaticamine.
 36. The lubricating oil additive composition of claim 35, whereinin copolymer (iii)(b), said copolymer (i) or copolymer (ii) or both arecontacted with the non-free radical catalyzed reaction product ofcompound (i)(a) and compound (i)(b) or (i)(c) in the presence ofcomponent (C).
 37. A method of improving soot dispersancy in an internalcombustion engine which comprises operating the engine with thelubricating oil composition comprising a major amount of oil oflubricating viscosity and an effective amount of the lubricating oiladditive composition of claim
 1. 38. The lubricating oil additivecomposition of claim 1, wherein said component (A)(i)(b) of saidcopolymer (A)(i) is a polyisobutene which comprises at least 50% of amethylvinylidene isomer.
 39. The lubricating oil additive composition ofclaim 1, wherein said component (A)(i)(b) of said copolymer (A)(i) is apolyisobutene which comprises at least 70% of a methylvinylidene isomer.